exe files blocked

what kind of virus it is and how can i get rid of it? every exe is file is constantly disabled like: "the file (name of aplication).exe is unable to find , verify the path and location". no aplication at all. only way to start any program is to open some file already created by this aplication, for example doc files or photoshop, and to use these created files as the starters of this aplication. it doesnt even work in safe mode. not even start->run->regedit.
thanx in advance

hello,
i downloaded fixswen.exe and it did the job. since then everything works more or less allright, but some damages seem to be apparent though. (for instance, nero needs to restart two times the burning process)
but, thank you very much, for your time and energy. keep going.
ancias

For damage to Windows, you can place your Windows CD in the drive, click Start > run, type in CMD, when the black window opens type in "sfc /scannow"

SFC (System File Checker, is a part of Windows File Protection and will replace any changed/damaged system files with a clean copy. SFC may not solve every problem, but it's a good start that anyone can do...

You may have to uninstall other programs that have developed hiccups, and then reinstall them.